BULLDOG SpaceKeeper Vertical – Installation Operation Maintenance Manual
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© Copyright 2013 CGC Group Inc Installation Operation Maintenance Manual is Subject to Change without Notice- Last Revised Oct 1, 2014
put into operation. If a cooling call is in place, it must be disengaged before the cause of the last alarm
shutdown can be identified.
OPERATION ALGORITHM
There are several control algorithms to prevent cycling and problematic operation. These are:
1.
Double Call – If thermostat connections or set up is incorrect resulting in a simultaneous call
for both heating and cooling, the unit will not operate. This condition can be observed on the
thermostat connection LEDs. (Note: A heat pump thermostat will present this scenario).
2.
Reverse Cycle Call – Poorly located automatic changeover thermostats (ie. thermostats mounted
on a wall opposite a discharge grill, or a thermostat in a doorway to outside) can trigger heating
and cooling mode changes many times an hour. The CGC controller has a 10-minute anti-mode
change timer when changing from cooling to heating operation. The controller will not accept a
change in mode until 10 minutes have elapsed since termination of the opposite call.
THERMOSTAT CONNECTIONS
The CGC control board has been designed to operate with most standard 24V AC thermostats. These are
powered from the CGC board with 24V AC and simply switch power ON to each of the Heat (W), Cool (Y),
Fan (G) or Aux (A). While most present day thermostats operate in this manner there are others that may
or may not work properly. The following should be checked out for satisfactory performance prior to
installing:
1.
Heat Pump Thermostat – Some heat pump units do not have heat relays (therefore are not
compatible with standard thermostats) and require “Heat Pump Thermostats”. These
thermostats call for both heating and cooling on one of the signal wires. These thermostats
are completely incompatible with CGC’s controller.
2.
Battery Powered Thermostats – These thermostats were developed as replacements for old
mercury bulb thermostats that had 4 wire connections while 24V electronic thermostats
required 5 wires. These will work with a CGC board, although CGC does not recommend them.
They require periodic battery replacement, which is something that should be avoided if
possible.
3.
Power Stealing Thermostats – This type of thermostat is electronic and was also developed as
a replacement for old mercury bulb thermostats. These too are problematic in that they bleed
a small amount of current down the signal wires and this may be interpreted as a signal for
heat or cool.
4.
Triac Switched Controllers – This is a commonly used switching device and all controllers
tested to date have functioned flawlessly. CGC recommends that prior to installation of a third
party supplied controller, it be checked for compatibility. CGC can confirm this.
5.
Relay Switched Controllers – This type of controller works well with CGC devices.
SHUTDOWN OUTPUT
